STC Duo Band Filters for DSLRs, Yeah or Nay

[glend]

Holiday online browsing this morning. The STC Duo Band Filters seem to produce some amazing images on OSC cameras. Does anyone have real world experience with these? Does the Hubble Pallette Synth really work?:question:

[AnakChan]

Here’s a sample pix of the STC Duo NB. I personally like it but I am curious on the Triad Quad Ultra NB (which is more than 2x the cost of the STC Duo NB).

Note, this NGC 7000 wasn’t tracked properly but it should give an idea. This is a combo (I forgot how many “usable” subs!) of 300 sec/sub.

Someone was supposed to release a tool/app/plug-in for the Hubble Palatte but don’t think he/she did. Anyhow processing in PI for this was a little PITA.

[ChrisV]

I've had one for two months now. I'm still mucking around with it. So far I've mostly processed as an OSC image. It gives cleaner images but not spectacular. Here's some examples.
https://www.astrobin.com/users/ChrisFC/

So now I've started trying narrow band processing. Never done this before. I will see how that goes. Steep learning curve but it looks promising.

There's also an interesting idas nb1 filter
https://www.cloudynights.com/topic/643748-new-idas-nb1-filter/

[RyanJones]

I've been drooling over the idea of one of these for a couple of months now and I'm borderline ready to take the plunge. I'd love to know what they are like with a DSLR. I can only seem to find images taken with Astro cameras.

[ChrisV]

Here's a comparison bteween the Duo filter and just a UV/IR filter
- First is with the STC Duo filter processed as a narrowband image. Split the R & GB channels and process as Halpha and OIII in pixinsight
- The second is just a UV-IR filter processed as OSC image

Both same camera & scope. And both about 6-7 hours of subs. 10min subs with duo filter and 2min subs with UV-IR.
The duo image still isn't great as I haven't got a great handle on narrowband processing yet.

[RyanJones]

Great comparison Chris. So using the STC Duo, you need longer subs ? ( I've read that ) but the move to 5 times as much ? Was that because you can or you have to ?

To be fair, with what I'm producing at the moment, I'd be extatic about either image. :thumbsup:

[glend]

Ryan, all narrowband acquistion requires longer subs, regardless of the camera used, because it is only allowing a thin slice of the spectrum through the filter, and in many cases there is not a lot of signal coming from the target, so time on target becomes important. When I shoot pure narrowband with my mono cooled camera I use 5 min subs as default.

Chris that Duo shot looks ok but the star colour needs work. I don't know anything about PI but I could fix it in Photoshop.

To be clear, i am only asking about the Duo for my Nikon D5300, i am very happy with the narrowband performance of the ASI1600MM-C; but the Nikon has a larger sensor that takes advantage of my wide field scope larger image circle.

[ChrisV]

Yes Glenn. I normally do 90-120sec subs with this camera. To get the same background level I needed 6-10min subs with the duo filter - which is about 15-20*RN^2.

Yep. Lousy star colour ... I got a lot learn processing this stuff.
Makes sense with your Nikon

[RyanJones]

Thank you Glen and Chris. Good to know :thumbsup:

[NorthernLight]

I ordered one last year and can say that it’s a real game changer for me, here in the backyard under urban light pollution. Even with the full moon up, I can image 240sec 80mm f/6 and get meaningful results. My camera is Baader modded and colour rendition is pretty much perfect. The stars are super tight and the contrast on nebulousity is amazing. The clip in filter is not as well built as the Astronomiks but it it works. I tried the UHC and the CLS filters prior but this one stands out. I have tried to process as NB’ s with channel splitting but haven’t had time to figure out how to do it properly. Anyway, even without it, the gain for me is remarkable and I keep the STC permanently in the camera. I’m sure a dedicated Astro cam with 3nm Astrodons put my setup in its place but until I upgrade, this is the way to go.

[ChrisV]

My sentiments exactly Max. I'm nearly getting there with narrow band processing. But just leaving it in the scope and treating it like any other osc filter - much cleaner images that seem well colour balanced. A game changer with my LP suburbs

[AnakChan]

Just FYI, NB filter options are expanding. IDAS will be releasing their NB2 and NB3 next month. More from DigiBorg’s site :-

https://digiborg.wordpress.com/2019/04/24/nebula-booster-nb2-and-nb3/